Severe tropical storm Khanun is no longer expected to head westward. It is now seen moving slowly east.

It has engulfed Okinawa Prefecture's main island region and Kagoshima Prefecture's Amami region.

Weather officials are urging caution, as chances are high that life-threatening landslides and floods will occur.

Bands of active rain clouds have formed over Okinawa. These could also develop in Amami and the southern parts of Kyushu through Monday morning.

Even light rains or winds could heighten the disaster risks in Okinawa and Amami, as both were hit hard by the storm's early approach.

The Japan Meteorological Agency says the storm is also packing strong gusts of wind.

Video taken Sunday in Yaese, on Okinawa's main island shows part of a building blown away by strong winds, blocking a road.

Okinawa Electric Power Company says more than 20,000 households were without electricity as of 5 p.m. on Sunday. Naha is distributing water as power outages have cut off supplies in some areas.

Humid air is expected to flow into the Pacific side of western and eastern Japan. Extremely heavy rain is expected to fall intermittently in those areas, even before Khanun approaches.